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183.Customers Who Never Order

183.Customers Who Never Order

难度:Easy

某网站包含两个表,Customers 表和 Orders 表。编写一个 SQL 查询,找出所有从不订购任何东西的客户。

Customers 表:
+----+-------+
| Id | Name |
+----+-------+
| 1 | Joe |
| 2 | Henry |
| 3 | Sam |
| 4 | Max |
+----+-------+
Orders 表:
+----+------------+
| Id | CustomerId |
+----+------------+
| 1 | 3 |
| 2 | 1 |
+----+------------+
例如给定上述表格,你的查询应返回:
+-----------+
| Customers |
+-----------+
| Henry |
| Max |
+-----------+

需要注意Orders表中的去重,

# Write your MySQL query statement below
SELECT Name as Customers from Customers WHERE Id NOT IN (SELECT DISTINCT CustomerId from Orders)